#include <stdio.h>
#include <inttypes.h>
#include <stdexcept>
#include "sdkconfig.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_chip_info.h"
#include "esp_flash.h"
#include "esp_system.h"
#include "esp_log.h"
#include "esp_event.h"

//
#include "common/constants.h"
#include "common/queue_defs.h"
#include "common/system_context.h"
#include "io/nvs_handler.h"
#include "io/fs_handler.h"
#include "info/info.h"
#include "display/eink_display_handler.h"
#include "display/lvgl_handler.h"
#include "ui/ui_handler.h"
#include "ui/apps/registry.h"
#include <tick/lv_tick.h>
#include "esp_lvgl_port.h"
#include "lvgl.h"
#include "network.h"
#include <esp_task_wdt.h>

#include "lvgl.h"

// nvs storage namespaces, 15 characters max
#define DEFAULT_STORAGE_NAMESPACE "storage"
#define TAG "Main"

extern "C" void app_main(void);

void init_queues(
  QueueHandle_t& touch_queue,
  EventGroupHandle_t& system_event_group,
  EventGroupHandle_t& system_lifecycle_event_group
);

void app_main(void) {
  display_chip_info();

  // Initialize default event loop early - required for UI events
  esp_err_t err = esp_event_loop_create_default();
  if (err != ESP_OK && err != ESP_ERR_INVALID_STATE) {
    ESP_LOGE(TAG, "Failed to create default event loop: %s", esp_err_to_name(err));
    vTaskDelay(5000 / portTICK_PERIOD_MS);
    return esp_restart();
  }
  ESP_LOGI(TAG, "Default event loop created.\n");

  QueueHandle_t touch_event_queue = NULL;
  EventGroupHandle_t system_event_group = NULL, system_lifecycle_event_group = NULL;

  init_queues(touch_event_queue, system_event_group, system_lifecycle_event_group);
  if (touch_event_queue == NULL || system_event_group == NULL || system_lifecycle_event_group == NULL) {
    ESP_LOGE("Main", "Failed to create one or more queues/event groups");
    vTaskDelay(5000 / portTICK_PERIOD_MS);
    return esp_restart();
  }
  ESP_LOGI(TAG, "Queues initialized.\n");

  //
  KVStorageHandler* kv_storage_handler = new NVSStorageHandler(
    DEFAULT_STORAGE_NAMESPACE
  );

  auto fs_handler = std::make_shared<LittleFSHandler>();
  esp_err_t fs_err = fs_handler->init("/littlefs");
  if (fs_err != ESP_OK) {
    ESP_LOGE(TAG, "Failed to initialize LittleFS: %s", esp_err_to_name(fs_err));
    vTaskDelay(5000 / portTICK_PERIOD_MS);
    return esp_restart();
  }

  auto wifi_handler = std::make_unique<WifiHandler>(fs_handler);
  NetworkHandler* network_handler = new NetworkHandler(std::move(wifi_handler));
  EInkDisplayHandler* display_handler = new EInkDisplayHandler();
  // Initialize display and touch
  // display_handler->init_devices(system_event_group);
  display_handler->init_devices();
  ESP_LOGI(TAG, "E-Ink display handler initialized.\n");
  // LVGL Handler
  std::unique_ptr<EInkDisplayHandler> display_uptr(display_handler);
  LVGLHandler lvgl_handler(std::move(display_uptr));
  err = lvgl_handler.initLVGL(system_event_group);
  if (err != ESP_OK) {
    ESP_LOGE(TAG, "Failed to initialize LVGL handler: %s", esp_err_to_name(err));
    vTaskDelay(5000 / portTICK_PERIOD_MS);
    return esp_restart();
  }

  //
  kv_storage_handler->init(system_event_group);
  network_handler->init(system_event_group);

  // Make network handler available to apps
  SystemContext::instance().set_network_handler(network_handler);

  //
  ESP_LOGI(TAG, "Waiting for system to be ready...\n");
  xEventGroupWaitBits(
    system_event_group,
    // DISPLAY_READY_BIT | STORAGE_READY_BIT | NETWORK_READY_BIT,
    DISPLAY_READY_BIT,
    // do not clear on exit, require explicit reset
    pdFALSE,
    pdTRUE,
    portMAX_DELAY
  );
  ESP_LOGI(TAG, "System is ready. Starting main application...\n");

  AppRegistry& app_registry = AppRegistry::instance();
  err = app_registry.init();
  if (err != ESP_OK) {
    ESP_LOGE(TAG, "Failed to initialize App Registry: %s", esp_err_to_name(err));
    vTaskDelay(5000 / portTICK_PERIOD_MS);
    return esp_restart();
  }
  UIHandler ui_handler;
  err = ui_handler.init();
  if (err != ESP_OK) {
    ESP_LOGE(TAG, "Failed to initialize UI handler: %s", esp_err_to_name(err));
    vTaskDelay(5000 / portTICK_PERIOD_MS);
    return esp_restart();
  }
  ESP_LOGI(TAG, "UI handler initialized.\n");

  // Allow LVGL system to stabilize before creating objects
  vTaskDelay(pdMS_TO_TICKS(100));

  // wait for shutdown signal
  ESP_LOGI(TAG, "Waiting for shutdown signal...\n");
  EventBits_t bits = xEventGroupWaitBits(
    system_lifecycle_event_group,
    SYSTEM_SHUTDOWN_BIT | SYSTEM_RESTART_BIT,
    // do not clear on exit, require explicit reset
    pdFALSE,
    pdFALSE,
    portMAX_DELAY
  );
  ESP_LOGI(TAG, "Shutdown signal received. Cleaning up...\n");

  // Show shutdown screen using the shutdown descriptor's app instance
  // ShutdownApp* shutdown_app = dynamic_cast<ShutdownApp*>(shutdown_descriptor->get_app_instance());
  // if (shutdown_app) {
  //   ui_handler.switch_app(shutdown_app);
  // }
  vTaskDelay(1000 / portTICK_PERIOD_MS);  // Display shutdown message briefly

  // Cleanup
  // ui_handler.deinit();
  // delete demo_descriptor;
  // delete shutdown_descriptor;
  // delete mtr_descriptor;

  vEventGroupDelete(system_event_group);
  vQueueDelete(touch_event_queue);
  ESP_LOGI(TAG, "Cleanup complete.\n");

  // handle shutdown or restart
  if (bits & SYSTEM_SHUTDOWN_BIT) {
    // if (shutdown_display_handler != nullptr) {
    //   ESP_LOGI(TAG, "Calling display shutdown handler...\n");
    //   shutdown_display_handler();
    // } else {
    //   ESP_LOGI(TAG, "No display shutdown handler to call.\n");
    // }
    ESP_LOGI(TAG, "System is shutting down.\n");
    fflush(stdout);
    // wait for start bit to be set again if future restart is desired, else expect manual power cycle
    EventBits_t bits = xEventGroupWaitBits(
      system_lifecycle_event_group,
      SYSTEM_START_BIT,
      pdFALSE,
      pdFALSE,
      portMAX_DELAY
    );
    if (bits & SYSTEM_START_BIT) {
      ESP_LOGI(TAG, "SYSTEM_START_BIT received, restarting system.\n");
    } else {
      ESP_LOGW(TAG, "No restart signal received, waiting for manual power cycle.\n");
      while (true) {
        vTaskDelay(portMAX_DELAY);
      }
    }
  } else if (bits & SYSTEM_RESTART_BIT) {
    // if (restart_display_handler != nullptr) {
    //   ESP_LOGI(TAG, "Calling display restart handler...\n");
    //   restart_display_handler();
    // } else {
    //   ESP_LOGI(TAG, "No display restart handler to call.\n");
    // }
    ESP_LOGI(TAG, "System is restarting.\n");
    fflush(stdout);
  } else {
    ESP_LOGW(TAG, "Unknown shutdown signal received. Restarting by default.\n");
    fflush(stdout);
  }

  return esp_restart();
}

void init_queues(
  QueueHandle_t& touch_queue,
  EventGroupHandle_t& system_event_group,
  EventGroupHandle_t& system_lifecycle_event_group
) {
  // Implementation of queue initialization
  touch_queue = xQueueCreate(10, sizeof(touch_event_t));
  system_event_group = xEventGroupCreate();
  system_lifecycle_event_group = xEventGroupCreate();
}